docs: def get_subgraph_by_second_neighbors(graph, nodes: Iterable[BaseEntity], filter_pathologies: bool = False):
      """Get a graph around the neighborhoods of the given nodes and expand to the neighborhood of those nodes.
  
      Returns none if none of the nodes are in the graph.
  
      :param pybel.BELGraph graph: A BEL graph
      :param nodes: An iterable of BEL nodes
      :param filter_pathologies: Should expansion take place around pathologies?
      :return: A BEL graph induced around the neighborhoods of the given nodes
      :rtype: Optional[pybel.BELGraph]
      """
      result = get_subgraph_by_neighborhood(graph, nodes)
  
      if result is None:
          return
  
      expand_all_node_neighborhoods(graph, result, filter_pathologies=filter_pathologies)
      return result